North Korea last month restarted ballistic missile tests for the first time in nearly a year and a half.

"But he's kept his word to me; that's very important", said Trump. I think North Korea has tremendous potential.

A February summit between Kim and Trump in Hanoi, Vietnam had been expected to at least lay out a path forward.

It's extremely hard to verify information about North Korea's ruling family. They had been accused of colluding with four North Koreans who prosecutors said had fled the country the day of the attack.

Trump and Kim Jong Un have had a hot-and-cold relationship as Washington and Pyongyang have negotiated over North Korea's development of nuclear weapons. "Here at the State Department we are ready and willing to continue engagement on working-level negotiations with the North Koreans". North Korea called it an illegal act that violated the spirit of the Singapore summit. But it later canceled the event.

In a poll commissioned by the Korea Foundation-Vrije Universiteit Brussel (KF-VUB) Korea chair and released to Reuters, most respondents in the US, Japan and Russian Federation said relations between Washington and Pyongyang were similar to what they were a year ago.

"I saw the information about the Central Intelligence Agency with respect to his brother or half-brother, and I would tell him that would not happen under my auspices, that's for sure", Trump said. Kim has said the United States has until the end of the year to offer mutually acceptable terms for a deal to salvage the diplomacy.

The sister of North Korean leader Kim Jong-un on Wednesday delivered a condolence message for former South Korean first lady Lee He-ho, the first high-level contact between the two countries in months. The expert said he was positive when it comes to future talks as Trump can use the talks for political purposes ahead of the presidential election.